Threaded lids are often overtightened and therefore difficult to manually remove from their containers. Apparatus intended to assist in such removal are described in U.S. Pat. Nos. 1,953,412; 2,058,949; 2,718,800; 2,837,947; 2,937,548; 3,280,664; 3,293,957; 3,724,296; 3,950,801; 4,171,650; 4,615,241; 4,833,948 and 5,003,844.